Firearms

I'm looking for some feedback on the gun rules I've cobbled together for 4e. Any suggestions will be greatly appreciated. If they relate to specific tweaks on the rules I've presented here all the better, but I'm interested on any work that's being done along these lines. I'm not married to this approach and want to see what's out there.

Thanks in advance... This is my first 4e material for public consumption so if anybody has tips on how I can better balance it, let me know.

FIREARM TRAINING [MULTICLASS]
Prerequisites: Dex 13, any martial classBenefit: You gain proficiency with firearms. When you hit with
your weapon, you can forgo dealing damage and daze the target
until the end of your next turn instead. On a critical hit, the target
is also knocked prone. (A little "Alright you Primitive Screwheads,
listen up! You see this? This... is my BOOMSTICK!" action with
everybody cringing and ducking for cover.)

FIREARM NOVICEPrerequisites: Firearm Training, 4th levelBenefit: You can swap one 3rd-level or higher encounter attack
power you know for the Kneecap attack power.

FIREARM EXPERTPrerequisites: Firearm Training, 8th levelBenefit: You can swap one 6th-level or higher utility power you
know for the Trick-shot attack power.

Trick-shot -- Feat PowerLinear thinking won't always bring down your prey... you know
how to ricochet bullets around corners, shoot chandeliers down
and thread a shot through tiny gaps.EncounterMinor Action - PersonalEffect: Ignore cover and superior cover the next time you make
a ranged attack with a firearm.

FIREARM SPECIALISTPrerequisites: Firearm Training, 10th levelBenefit: You can swap one 9th-level or higher daily attack
power you know for the Stand-and-Deliver attack power.

Stand-and-Deliver -- Feat PowerWhen you *must* get the shot, sometimes you throw personal
safety to the wind. Daily - Stance, Weapon
Standard Action - Ranged weaponRequirement: You must be wielding a firearm.Target: One creatureAttack: Dexterity +2 vs. ACHit: 2[W] + Dexterity modifier + Wisdom modifier damage.Effect: Until the stance ends, the range of your weapon attacks
is extended by 5/10 squares and you gain the Aim utility power.
You also grant combat advantage to all enemies.

Aim -- Stance powerHeedless of the roil of battle around you and your instincts to
flee from harm's way, you instead stand and deliver!At-Will - Stance, Weapon
Minor Action - PersonalRequirement: You must be wielding a firearm.Effect: Add your Wisdom modifier to your damage.

It is by caffeine alone I set my mind in motion. It is by the Beans of Java that thoughts acquire speed, the hands acquire shaking, the shaking becomes a warning. It is by caffeine alone I set my mind in motion.